Since the 1960s, more than 350,000 new chemicals have been introduced into the lives of humans and domestic animals. Many of them have become part of modern life and some are affecting nature as pollutants. Yet, our comprehension of their potential health risks for both humans and animals remains partial. The "epithelial barrier theory" suggests that genetic predisposition and exposure to diverse factors damaging the epithelial barriers contribute to the emergence of allergic and autoimmune conditions. Impaired epithelial barriers, microbial dysbiosis, and tissue inflammation have been observed in a high number of mucosal inflammatory, autoimmune and neuropsychiatric diseases, many of which showed increased prevalence in the last decades. Pets, especially cats and dogs, share living spaces with humans and are exposed to household cleaners, personal care products, air pollutants, and microplastics. The utilisation of cosmetic products and food additives for pets is on the rise, unfortunately, accompanied by less rigorous safety regulations than those governing human products. In this review, we explore the implications of disruptions in epithelial barriers on the well-being of companion animals, drawing comparisons with humans, and endeavour to elucidate the spectrum of diseases that afflict them. In addition, future research areas with the interconnectedness of human, animal, and environmental well-being are highlighted in line with the "One Health" concept.

• Klíčová slova
• companion animals, epigenetics, epithelial barrier, exposome, microbiota, skin,
• MeSH
• domácí zvířata * imunologie   MeSH
• epitel imunologie   MeSH
• kočky MeSH
• lidé MeSH
• psi MeSH
• vystavení vlivu životního prostředí škodlivé účinky   MeSH
• zvířata MeSH
• Check Tag
• kočky MeSH
• lidé MeSH
• psi MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Outer membrane vesicles (OMVs) carrying virulence factors of enterohemorrhagic Escherichia coli (EHEC) are assumed to play a role in the pathogenesis of life-threatening hemolytic uremic syndrome (HUS). However, it is unknown if and how OMVs, which are produced in the intestinal lumen, cross the intestinal epithelial barrier (IEB) to reach the renal glomerular endothelium, the major target in HUS. We investigated the ability of EHEC O157 OMVs to translocate across the IEB using a model of polarized Caco-2 cells grown on Transwell inserts and characterized important aspects of this process. Using unlabeled or fluorescently labeled OMVs, tests of the intestinal barrier integrity, inhibitors of endocytosis, cell viability assay, and microscopic techniques, we demonstrated that EHEC O157 OMVs translocated across the IEB. OMV translocation involved both paracellular and transcellular pathways and was significantly increased under simulated inflammatory conditions. In addition, translocation was not dependent on OMV-associated virulence factors and did not affect viability of intestinal epithelial cells. Importantly, translocation of EHEC O157 OMVs was confirmed in human colonoids thereby supporting physiological relevance of OMVs in the pathogenesis of HUS.

• Klíčová slova
• Caco-2 cells, enterohemorrhagic Escherichia coli, hemolytic uremic syndrome, human colonoids, intestinal epithelial barrier, outer membrane vesicles, translocation,
• Publikační typ
• časopisecké články MeSH

We aimed to investigate the effects of brain-derived neurotrophic factor (BDNF) on apoptosis of intestinal epithelial cells (IECs) and alterations of intestinal barrier integrity using BDNF knock-out mice model. Colonic tissues from BDNF(+/+) mice and BDNF(+/-) mice were prepared for this study. The integrity of colonic mucosa was evaluated by measuring trans-mucosa electrical resistance and tissue conductance in Ussing chamber. The colonic epithelial structure was analyzed by transmission electron microscopy. Apoptosis involvement was determined with TUNEL staining, active caspase-3 immunostaining and Western blotting for the protein expression of active caspase-3, Bax and Bcl-2. The expression levels and distribution of tight junction proteins were evaluated by immunohistochemistry or Western blots. Compared with BDNF(+/+) mice, BDNF(+/-) mice displayed impaired integrity and ultrastructure alterations in their colonic mucosa, which was characterized by diminished microvilli, mitochondrial swelling and epithelial cells apoptosis. Altered intestinal barrier function was linked to excessive apoptosis of IECs demonstrated by the higher proportion of TUNEL-positive apoptotic cells and enhanced caspase activities in BDNF(+/-) mice. Increased expression of Bax and claudin-2 proteins and reduced Bcl-2 and tight junction proteins (occludin, ZO-1 and claudin-1) expression were also detected in the colonic mucosa of BDNF(+/-) mice. BDNF may play a role in the maintenance of intestinal barrier integrity via its anti-apoptotic properties.

• MeSH
• apoptóza * MeSH
• epitelové buňky fyziologie   MeSH
• kaspasa 3 metabolismus   MeSH
• mozkový neurotrofický faktor fyziologie   MeSH
• myši inbrední C57BL MeSH
• myši knockoutované MeSH
• myši MeSH
• proteiny těsného spoje metabolismus   MeSH
• střevní sliznice metabolismus   ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kaspasa 3 MeSH
• mozkový neurotrofický faktor MeSH
• proteiny těsného spoje MeSH

Calpain2 is a conventional member of the non-lysosomal calpain protease family that has been shown to affect the dynamics of focal and cell-cell adhesions by proteolyzing the components of adhesion complexes. Here, we inactivated calpain2 using CRISPR/Cas9 in epithelial MDCK cells. We show that depletion of calpain2 has multiple effects on cell morphology and function. Calpain2-depleted cells develop epithelial shape, however, they cover a smaller area, and cell clusters are more compact. Inactivation of calpain2 enhanced restoration of transepithelial electrical resistance after calcium switch, decreased cell migration, and delayed cell scattering induced by HGF/SF. In addition, calpain2 depletion prevented morphological changes induced by ERK2 overexpression. Interestingly, proteolysis of several calpain2 targets, including E-cadherin, β-catenin, talin, FAK, and paxillin, was not discernibly affected by calpain2 depletion. Taken together, these data suggest that calpain2 regulates the stability of cell-cell and cell-substratum adhesions indirectly without affecting the proteolysis of these adhesion complexes.

• Klíčová slova
• Actin, Adherens junctions, Calpains, Cell scattering, ERK, Epithelial polarity, Focal adhesions, HGF/SF, Migration, Proteases, Tight junctions, Transepithelial electrical resistance,
• MeSH
• beta-katenin metabolismus   MeSH
• buněčná adheze * MeSH
• buňky MDCK MeSH
• CRISPR-Cas systémy MeSH
• epitelové buňky * metabolismus   cytologie   MeSH
• hepatocytární růstový faktor metabolismus   MeSH
• kadheriny metabolismus   MeSH
• kalpain * metabolismus   MeSH
• mitogenem aktivovaná proteinkinasa 1 metabolismus   MeSH
• pohyb buněk MeSH
• proteolýza MeSH
• psi MeSH
• vápník metabolismus   MeSH
• zvířata MeSH
• Check Tag
• psi MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• beta-katenin MeSH
• hepatocytární růstový faktor MeSH
• kadheriny MeSH
• kalpain * MeSH
• mitogenem aktivovaná proteinkinasa 1 MeSH
• vápník MeSH

• Klíčová slova
• Aspergillus fumigatus, IL-17 immunity, epithelial barrier, lung infection, lung organoids,
• MeSH
• infekce dýchací soustavy imunologie   MeSH
• interleukin-17 imunologie   MeSH
• lidé MeSH
• organoidy imunologie   MeSH
• plíce imunologie   MeSH
• receptory interleukinu-17 imunologie   MeSH
• respirační sliznice imunologie   MeSH
• signální transdukce MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• interleukin-17 MeSH
• receptory interleukinu-17 MeSH

PURPOSE: To document the expression of apical-basal polarity (ABP) determinants in the mouse corneal epithelium (CE) and elucidate the functions of Pard3 in establishment and maintenance of ABP, stratification, homeostasis, and barrier function in the CE. METHODS: Pard3Δ/ΔC mice (Pard3LoxP/LoxP; Aldh3A1-Cre/+) with cornea-specific Pard3 ablation were generated by breeding Aldh3A1-Cre/+ with Pard3LoxP/LoxP mice. The control (Aldh3A1-Cre/+ or Pard3LoxP/LoxP alone) and Pard3Δ/ΔC corneal histology, ocular surface properties, barrier function, and actin cytoskeleton were assessed by Haematoxylin and Eosin staining of paraformaldehyde-fixed, paraffin-embedded tissues, scanning electron microscopy, fluorescein staining, and phalloidin staining, respectively. The expression of specific markers of interest was evaluated by qRT-PCR, immunoblots and immunofluorescent staining. RESULTS: Dynamic changes were observed in the expression and localization of ABP determinants as the CE stratified and matured between post-natal day 5 (PN5) and PN52. Adult Pard3Δ/ΔC CE contained fewer cell layers with rounded basal cells, and loosely adherent superficial cells lacking microplicae. Adult Pard3Δ/ΔC CE also displayed impaired barrier function with decreased expression of tight junction, adherens junction, and desmosome components, disrupted actin cytoskeletal organization, increased proliferation, and upregulation of transcription factors that drive epithelial-mesenchymal transition (EMT). CONCLUSIONS: Disruption of ABP in Pard3Δ/ΔC CE, altered expression of cell junction complex components and disorganized actin cytoskeleton, increased cell proliferation, and upregulated EMT transcription factors suggest that the ABP-determinant Pard3 promotes CE features while suppressing mesenchymal cell fate. Collectively, these results elucidate that Pard3-mediated ABP is essential for CE stratification, homeostasis and barrier function.

• Klíčová slova
• Apical-basal polarity, Barrier function, Corneal epithelium, Par3, Par6, Pard3, Stratification, Tight junction,
• MeSH
• adaptorové proteiny signální transdukční * MeSH
• cytoskelet * metabolismus   MeSH
• homeostáza fyziologie   MeSH
• mikroskopie elektronová rastrovací MeSH
• myši MeSH
• polarita buněk * fyziologie   MeSH
• rohovkový epitel * metabolismus   ultrastruktura   MeSH
• těsný spoj * metabolismus   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adaptorové proteiny signální transdukční * MeSH

A steady rise in the number of poly-sensitized patients has increased the demand for effective prophylactic strategies against multi-sensitivities. Probiotic bacteria have been successfully used in clinics and experimental models to prevent allergic mono-sensitization. In the present study, we have investigated whether probiotic bacteria could prevent poly-sensitization by imprinting on the immune system early in life. We used two recombinant variants of probiotic Escherichia coli Nissle 1917 (EcN): i) EcN expressing birch and grass pollen, poly-allergen chimera construct (EcN-Chim), and ii) an "empty" EcN without allergen expression (EcN-Ctrl). Conventional mice (CV) were treated with either EcN-Chim or EcN-Ctrl in the last week of the gestation and lactation period. Gnotobiotic mice received one oral dose of either EcN-Chim or EcN-Ctrl before mating. The offspring from both models underwent systemic allergic poly-sensitization and intranasal challenge with recombinant birch and grass pollen allergens (rBet v 1, rPhl p 1, and rPhl p 5). In the CV setting, the colonization of offspring via treatment of mothers reduced allergic airway inflammation (AAI) in offspring compared to poly-sensitized controls. Similarly, in a gnotobiotic model, AAI was reduced in EcN-Chim and EcN-Ctrl mono-colonized offspring. However, allergy prevention was more pronounced in the EcN-Ctrl mono-colonized offspring as compared to EcN-Chim. Mono-colonization with EcN-Ctrl was associated with a shift toward mixed Th1/Treg immune responses, increased expression of TLR2 and TLR4 in the lung, and maintained levels of zonulin-1 in lung epithelial cells as compared to GF poly-sensitized and EcN-Chim mono-colonized mice. This study is the first one to establish the model of allergic poly-sensitization in gnotobiotic mice. Using two different settings, gnotobiotic and conventional mice, we demonstrated that an early life intervention with the EcN without expressing an allergen is a powerful strategy to prevent poly-sensitization later in life.

• Klíčová slova
• BALB/c, Escherichia coli Nissle 1917, allergic poly-sensitization, germ-free, hygiene hypothesis, mouse model, mucosal tolerance,
• MeSH
• alergeny imunologie   MeSH
• alergie imunologie   MeSH
• antigeny rostlinné imunologie   MeSH
• bříza imunologie   MeSH
• epitelové buňky imunologie   MeSH
• Escherichia coli imunologie   MeSH
• gnotobiologické modely imunologie   MeSH
• homeostáza imunologie   MeSH
• imunitní systém imunologie   MeSH
• lipnicovité imunologie   MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• probiotika aplikace a dávkování   MeSH
• pyl imunologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alergeny MeSH
• antigeny rostlinné MeSH

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an RNA virus responsible for coronavirus disease 2019 (COVID-19). While SARS-CoV-2 primarily targets the lungs and airways, it can also infect other organs, including the central nervous system (CNS). The aim of this study was to investigate whether the choroid plexus could serve as a potential entry site for SARS-CoV-2 into the brain. Tissue samples from 24 deceased COVID-19-positive individuals were analyzed. Reverse transcription real-time PCR (RT-qPCR) was performed on selected brain regions, including the choroid plexus, to detect SARS-CoV-2 viral RNA. Additionally, immunofluorescence staining and confocal microscopy were used to detect and localize two characteristic proteins of SARS-CoV-2: the spike protein S1 and the nucleocapsid protein. RT-qPCR analysis confirmed the presence of SARS-CoV-2 viral RNA in the choroid plexus. Immunohistochemical staining revealed viral particles localized in the epithelial cells of the choroid plexus, with the spike protein S1 detected in the late endosomes. Our findings suggest that the blood-cerebrospinal fluid (B-CSF) barrier in the choroid plexus serves as a route of entry for SARS-CoV-2 into the CNS. This study contributes to the understanding of the mechanisms underlying CNS involvement in COVID-19 and highlights the importance of further research to explore potential therapeutic strategies targeting this entry pathway.

• Klíčová slova
• COVID‐19, SARS‐CoV‐2, blood‐cerebrospinal fluid barrier, choroid plexus, neuroinvasion,
• MeSH
• COVID-19 * virologie   patologie   MeSH
• dospělí MeSH
• fosfoproteiny MeSH
• glykoprotein S, koronavirus metabolismus   genetika   MeSH
• hematoencefalická bariéra * virologie   MeSH
• internalizace viru * MeSH
• koronavirové nukleokapsidové proteiny MeSH
• lidé středního věku MeSH
• lidé MeSH
• mozek virologie   MeSH
• plexus chorioideus * virologie   patologie   MeSH
• RNA virová genetika   MeSH
• SARS-CoV-2 * fyziologie   genetika   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fosfoproteiny MeSH
• glykoprotein S, koronavirus MeSH
• koronavirové nukleokapsidové proteiny MeSH
• nucleocapsid phosphoprotein, SARS-CoV-2 MeSH Prohlížeč
• RNA virová MeSH
• spike protein, SARS-CoV-2 MeSH Prohlížeč

The airway epithelium restricts the penetration of inhaled pathogens into the underlying tissue and plays a crucial role in the innate immune defense against respiratory infections. The whooping cough agent, Bordetella pertussis, adheres to ciliated cells of the human airway epithelium and subverts its defense functions through the action of secreted toxins and other virulence factors. We examined the impact of B. pertussis infection and of adenylate cyclase toxin-hemolysin (CyaA) action on the functional integrity of human bronchial epithelial cells cultured at the air-liquid interface (ALI). B. pertussis adhesion to the apical surface of polarized pseudostratified VA10 cell layers provoked a disruption of tight junctions and caused a drop in transepithelial electrical resistance (TEER). The reduction of TEER depended on the capacity of the secreted CyaA toxin to elicit cAMP signaling in epithelial cells through its adenylyl cyclase enzyme activity. Both purified CyaA and cAMP-signaling drugs triggered a decrease in the TEER of VA10 cell layers. Toxin-produced cAMP signaling caused actin cytoskeleton rearrangement and induced mucin 5AC production and interleukin-6 (IL-6) secretion, while it inhibited the IL-17A-induced secretion of the IL-8 chemokine and of the antimicrobial peptide beta-defensin 2. These results indicate that CyaA toxin activity compromises the barrier and innate immune functions of Bordetella-infected airway epithelia.

• Klíčová slova
• Bordetella pertussis, CyaA, adenylate cyclase toxin, airway epithelia, antimicrobial peptides, cyclic AMP, epithelial cells, immunomodulatory cytokines, tight junctions,
• MeSH
• adenylátcyklasový toxin genetika   metabolismus   toxicita   MeSH
• AMP cyklický metabolismus   MeSH
• Bordetella pertussis genetika   metabolismus   MeSH
• bronchy cytologie   metabolismus   mikrobiologie   MeSH
• cytoskelet metabolismus   MeSH
• epitelové buňky metabolismus   mikrobiologie   MeSH
• interleukin-6 metabolismus   MeSH
• lidé MeSH
• mucin 5AC metabolismus   MeSH
• pertuse genetika   metabolismus   mikrobiologie   MeSH
• signální transdukce účinky léků   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adenylátcyklasový toxin MeSH
• AMP cyklický MeSH
• interleukin-6 MeSH
• mucin 5AC MeSH

Mucosal surfaces covered by a layer of epithelial cells represent the largest and most critical interface between the organism and its environment. The barrier function of mucosal surfaces is performed by the epithelial layer and immune cells present in the mucosal compartment. As recently found, epithelial cells, apart from their participation in absorptive, digestive and secretory processes perform more than a passive barrier function and are directly involved in immune processes. Besides the well known role of epithelial cells in the transfer of polymeric immunoglobulins produced by lamina propria B lymphocytes to the luminal content of mucosals (secretory Igs), these cells were found to perform various other immunological functions, to interact with other cells of the immune system and to induce an efficient inflammatory response to microbial invasion: enzymic processing of dietary antigens, expression of class I and II MHC antigens, presentation of antigens to lymphocytes, expression of adhesive molecules mediating interaction with intraepithelial lymphocytes and components of extracellular matrix, production of cytokines and probable participation in extrathymic T cell development of intraepithelial lymphocytes. All these functions were suggested to influence substantially the mucosal immune system and its response. Under immunopathological conditions, e.g. during infections and inflammatory bowel and celiac diseases, both epithelial cells and intraepithelial lymphocytes participate substantially in inflammatory reactions. Moreover, enterocytes could become a target of mucosal immune factors. Mucosal immunosurveillance function is of crucial importance in various pathological conditions but especially in the case of the most frequent malignity occurring in the intestinal compartment, i.e. colorectal carcinoma. Proper understanding of the differentiation processes and functions of epithelial cells in interaction with other components of the mucosal immune system is therefore highly desirable.

• MeSH
• autoimunitní nemoci imunologie   patologie   MeSH
• Bacteria imunologie   MeSH
• celiakie imunologie   patologie   MeSH
• cytokiny fyziologie   MeSH
• dospělí MeSH
• epitel imunologie   MeSH
• epitelové buňky MeSH
• houby imunologie   MeSH
• idiopatické střevní záněty imunologie   patologie   MeSH
• imunoglobuliny imunologie   MeSH
• integriny fyziologie   MeSH
• kolorektální nádory imunologie   patologie   MeSH
• lidé MeSH
• lymfoidní tkáň cytologie   imunologie   MeSH
• membránové glykoproteiny fyziologie   MeSH
• myši knockoutované MeSH
• myši MeSH
• Peyerovy pláty imunologie   MeSH
• prezentace antigenu MeSH
• střeva mikrobiologie   MeSH
• střevní sliznice cytologie   imunologie   MeSH
• zvířata MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• cytokiny MeSH
• imunoglobuliny MeSH
• integriny MeSH
• membránové glykoproteiny MeSH